Drill-bit



(No Model.)

J. T. SNYDER. DRILL BIT.

No. 444,026. Patented'Jan. 6, 1891.

UNITED STATES PATENT FFICE.

JOHN T. SNYDER, OF LUZERNE, PENNSYLVANIA.

DRILL-BIT.

SPECIFICATION forming part of Letters Patent No. 444,026, dated January 6, 1891.

Application filed August 1, 1890. Serial No. 360,691. (No model.)

To all whom it may concern.-

Be it known that I, JOHN T. SNYDER, a citizen of the United States, residing at Luzerne, in the county of Luzerne and State of Pennsylvania, have invented a new and useful Drill-Bit, of which the following is a specification. w

This invention relates to stone-working, and more particularly to the drill-bits used therein; and the object of the same is to provide a bit-head that will accommodate doubleended bits both for boring and for breaking the core.

To this end the invention consists of the de' tails of construction, hereinafter more fully described, and illustrated in the drawings,in which Figure 1 is a side elevation of a drilling apparatus with my improved drilling-bit shown in connection therewith. Fig. 2 is an enlarged perspective view of the head with the bits in place therein. Fig. 3 is a plan view of the same with the core-bit turn ed with its point in the opposite direction. Fig. 4 is a perspective view of the head with the bits removed therefrom. Fig. 5 is an end view of the head. Fig. 6 shows perspective views of the bits.

Referring to the said drawings, the letter A indicates the auger; B, the screw-rod connected thereto, and O the hand-brace for operating the bit-head H.

D is a brace or lever supporting a nut N which engages the screw-rod, and is common in this art and needs no further explanation here.

Coming now to the present invention, said head H is provided with side grooves S of dovetailed cross-section, as best seen in Fig. 5, and within these grooves, at one side thereof, are lugs L. The boring-bits O are doubleended, and each is provided with a notch or shoulder R, which when the bit is inserted in the groove S abuts against the lug and holds the bit in place, as will be understood. In the operative or front end of the head H is a transverse slot T, as seen in Fig. 4, and in this slot is seated the core-bit K. The latter has a U-shaped body U, whose sides are extended into points P at opposite ends of the body. By this construction either point may be brought forward, and the point in use may stand to the front or to the rear of a single boring-bit when but one is used, as seen in Fig. 3. The core-bit is merely seated in the transverse slot, and the pressure of the core against the same keeps it in place. The function of this bit,-as will be clear, is to break and crush the core formed by the boring bit or bits, whereby the said core may be passed out of the hole being bored.

When any of the bits become dulled by constant use. the head is Withdrawn from the hole being bored and the dull bit turned end for end, whereby a fresh and sharp point will be presented, and when both ends are dulled the entire bit is removed and a sharp one substituted. The shoulder R in the side of each boring bit abuts against the lug L and prevents the dulling of the rearmost point while the bit is in place. The body of the core-bit body rests in the bottom of the transverse notch, whereby its rearmost point is not dulled.

What I claim as the salient points of this invention are l. The herein-described boring-tool, the same comprising a head H, having dovetailed grooves S in its sides, each groove containing a lug L at one side thereof, and boring-bits O, removably seated in said grooves and each having boring-faces at its ends, and shoulders R adjacent the same impinging against said lugs, as and for the purpose set forth.

2. In a boring-tool, the combination, with the head H, provided with the transverse slot T in its front end, and the side boring-bits O, detachably connected to said head, of the core-bit K, comprising a U-shaped body U, whose sides are extended from opposite ends thereof into points P, said body being detachably seated in said transverse slot, as and for the purpose set forth.

3. In a boring-tool, the combination, with the head H, having dovetailed side grooves S and a transverse slot T in its front end, lugs L in said side slots, and boring-bits O, removably seated in said side grooves and having shoulders R engaging said lugs, of

the core-bit K, comprising a U-shaped body U, whose sides are extended from opposite I ends thereof into points P, said body being 5 detachably seated in said transverse slot, as and for the purpose hereinhefore set forth.

In testimony that I claim the foregoing as I my own I have hereto aflixed my signature in presence of two witnesses.

JOHN T. SNYDER.

Witnesses:

WM. J. TREMBATH, AARON ANDREWS. 

